title: Methotrexate: mechanism of action in rheumatoid arthritis.
abstract: Most studies of immune function in rheumatoid arthritis (RA) patients treated with methotrexate (MTX) show only marginal effects on humoral or cellular immune responses. These include measurements of lymphocyte subsets, proliferative responses to mitogens, immunoglobulin production, rheumatoid factor and immune complexes. The mechanism of action of MTX in RA might be more antiinflammatory than immunosuppressive. This is supported by the rapid clinical response to drug treatment and by data from in vitro and animal studies. The inhibition of interleukin-1 (IL-1) activity or other inflammatory cytokines by MTX may play an important role in the antiinflammatory effect of MTX. MTX effects in RA are not fully understood and further studies are needed to clarify its mechanism of action. MTX has crucial effects on the cascade of events initiated by some cytokines (IL-1, IL-6, tumor necrosis factor), which plays a major role in RA and other inflammatory diseases.
authors.affiliation: Department of Rheumatology, Ichilov Hospital, Tel-Aviv University, Sackler School of Medicine, Israel.
authors.forename: R
authors.initials: R
authors.lastname: Segal
authors.forename: M
authors.initials: M
authors.lastname: Yaron
authors.forename: B
authors.initials: B
authors.lastname: Tartakovsky
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D000917:Antibody Formation / Q000187:drug effects; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D003094:Collagen / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism; D005492:Folic Acid / Q000378:metabolism; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects; D008727:Methotrexate / Q000627:therapeutic use*; D009000:Monocytes / Q000473:pathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016207:Cytokines; D003094:Collagen; D005492:Folic Acid; D010450:Endopeptidases; D008727:Methotrexate